Production of negative hydrogen ions using a low-pressure reflex discharge source

• Autorzy: Toader E.
• Konferencja: Proceedings of the 2nd IAEA Research Co-ordination Meeting of the Co-ordinated Research Project on Dense Magnetized Plasma 1-3 June 2005, Kudowa Zdrój, Poland
• Języki publikacji: EN

Abstrakty

EN

In this paper we analyze the possibility to use the reflex discharge plasma as a volume source of negative hydrogen ions. The basic internal parameters like the temperature Te and the density ne of the electrons, the density ni of the positive hydrogen ions, the density n- of the negative hydrogen ions, and the negative ion fraction n-/ne are measured and discussed. The operating conditions are optimized within the pressure range 0.1-10 Pa, the discharge power 20-140 watt, and the magnetic field 0-150 gauss. The experiment shows that the enhanced magnetic ionization is the most effective within the pressure range from 0.7 to 4.0 Pa. When p ť 1 Pa the cold electron temperature Te is 0.77 eV, the cold electron density ne is 4.2 ´ 10 18 m-3 and the negative ion density n- is as high as 0.8 x 10 17 m-3. The negative ion fraction n-/ne increases from 1.4% for p = 0.1 Pa to almost 2.2% within the pressure range 1-4 Pa. The positive ion density scales with the power, while the negative ion density and the negative ion fraction seems to saturate at higher power levels.

Słowa kluczowe

EN

magnetized plasma; negative ions; plasma sources

• Wydawca: Institute of Nuclear Chemistry and Technology
• Czasopismo: Nukleonika
• Rocznik: 2006
• Tom: Vol. 51, nr 1
• Strony: 29--35
• Opis fizyczny: Bibliogr. 18, rys.

Twórcy

autor

Toader E.

• Faculty of Physics, University of Bucharest, Box MG-11, 077125 Bucharest-Magurele, Romania, Tel.: [phone] ext. 134, Fax: [phone],,

Bibliografia

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